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Badger Arms
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I'm going to disagree on principle, not experience here. Does the 10mm have problems with lug damage? The lugs seem to take much less stress than you are leading on.
45 Super Conversion Parts
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1911Tuner
Moderator Emeritus
re: Stresses(Long)
I'm going to disagree on principle, not experience here. Does the 10mm have problems with lug damage? The lugs seem to take much less stress than you are leading on.
Howdy Badger,
I'll take a little different approach at this question...I may repeat some of that which I've already written.
ANY high-pressure round is going to make lug engagement more critical...
even the 9mm and .38 Super. Add the momentum/recoil impetus of
a heavier bullet...and it becomes even more so.
Study the locking lugs in the slide and on the barrel for a minute.
Even with 100% engagement...AND assuming that both lugs are bearing an equal share of the load horizontally(Which many factory-installed barrels don't)...there's not a lot of meat there to absorb the pounding of the 10mm and the .45 Super at best.
Reduce that vertical engagement by 25%...which many factory-fitted barrels
do...and you've reduced the strength of that lockup by 25%...again assuming equal horizontal lockup. If both aren't bearing an equal share of the load on a horizontal plane AND vertical engagement...the strength of
the lockup is further reduced.
Don't assume that because there are two lugs that both are bearing
half the load. Don't assume that because the lugs on the barrel and in
the slide are a given height/depth...that they are vertically meshed for
100% of their depth and height. You may get lucky, but don't bet on it.
Think of the gears in a transmission. If your shift fork were bent, and the maximum engagement between first gear and its mate in the cluster was
about 50 or 60 or even 70% of full mesh...and you revved the engine to 3,000 RPMs and sidestepped the clutch...what do you think would happen? It works on the same principle. The lugs on the slide and barrel
are very much like gears. They mesh. They absorb shock loads. If
they aren't completely meshed when that shock load hits...they won't live very long.
Remember that the recoil spring doesn't have a thing to do with how well the lugs bear up under the shock. If it did, the spring in a 10mm would be
so strong that you probably couldn't rack the slide unless the slide were so heavy that it would make carrying the gun impractical. That's why we don't
see major caliber autopistols with a straight blowback design.
And, to answer your question...Yes. I've seen a few Delta Elites with sheared lugs. I've also seen a few .45s...and the usual cause was insufficient lug engagement in the vertical and horizontal planes...
Another frequent cause is the location of the rear of the lower lug in relation to the impact surface in the frame...but that's a mechanical timing
issue that occurs after the pressures have dropped.
Barrel fit is the key to a long and happy life in any 1911, regardless of
caliber. When the pressures go up, it gets even more critical.
Luck!
Tuner
I'm going to disagree on principle, not experience here. Does the 10mm have problems with lug damage? The lugs seem to take much less stress than you are leading on.
Howdy Badger,
I'll take a little different approach at this question...I may repeat some of that which I've already written.
ANY high-pressure round is going to make lug engagement more critical...
even the 9mm and .38 Super. Add the momentum/recoil impetus of
a heavier bullet...and it becomes even more so.
Study the locking lugs in the slide and on the barrel for a minute.
Even with 100% engagement...AND assuming that both lugs are bearing an equal share of the load horizontally(Which many factory-installed barrels don't)...there's not a lot of meat there to absorb the pounding of the 10mm and the .45 Super at best.
Reduce that vertical engagement by 25%...which many factory-fitted barrels
do...and you've reduced the strength of that lockup by 25%...again assuming equal horizontal lockup. If both aren't bearing an equal share of the load on a horizontal plane AND vertical engagement...the strength of
the lockup is further reduced.
Don't assume that because there are two lugs that both are bearing
half the load. Don't assume that because the lugs on the barrel and in
the slide are a given height/depth...that they are vertically meshed for
100% of their depth and height. You may get lucky, but don't bet on it.
Think of the gears in a transmission. If your shift fork were bent, and the maximum engagement between first gear and its mate in the cluster was
about 50 or 60 or even 70% of full mesh...and you revved the engine to 3,000 RPMs and sidestepped the clutch...what do you think would happen? It works on the same principle. The lugs on the slide and barrel
are very much like gears. They mesh. They absorb shock loads. If
they aren't completely meshed when that shock load hits...they won't live very long.
Remember that the recoil spring doesn't have a thing to do with how well the lugs bear up under the shock. If it did, the spring in a 10mm would be
so strong that you probably couldn't rack the slide unless the slide were so heavy that it would make carrying the gun impractical. That's why we don't
see major caliber autopistols with a straight blowback design.
And, to answer your question...Yes. I've seen a few Delta Elites with sheared lugs. I've also seen a few .45s...and the usual cause was insufficient lug engagement in the vertical and horizontal planes...
Another frequent cause is the location of the rear of the lower lug in relation to the impact surface in the frame...but that's a mechanical timing
issue that occurs after the pressures have dropped.
Barrel fit is the key to a long and happy life in any 1911, regardless of
caliber. When the pressures go up, it gets even more critical.
Luck!
Tuner
Clark
Member
CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The High Road, nor the staff of THR assume any liability for any damage or injury resulting from use of this information.
When I read the 3 realguns articles on 45 Super back in 2000, a great big, AHAH!!" went off in my head.
There is a continious range of increasing pressure of 45 acp from:
1) What will just cycle the action with a soft recoil spring to 45acp
2) 45acp
3) 45acp +P
4) 45 Super
5) 460 Rowloand equivalent loads
6) Beyond 460 Rowland loads
I have done all of these, and points in between in .1 gr increments.
The things to watch are:
1) Ammo must be powerfull enough to cylcle the action with that spring and slide mass or it will jam.
2) Ammo must be too much more than enough or the slide will batter the frame.
3) The case must be supported enough for the pressure, or the case will bulge, or worse.
Following these guide lines, I have found the level that is right for my 45acps:
1) Mauser Rifle, beyond 460 Rowland
2) Patriot pistol, 460 Rowland
3) Colt Commander, between 45 Super and 460 Rowland
4) Para Ord P10, 45 Super, Starline +P brass, 1.275", 155 gr SWC
I have had to put serious recoil springs in the Patriot and the Commander.
When I read the 3 realguns articles on 45 Super back in 2000, a great big, AHAH!!" went off in my head.
There is a continious range of increasing pressure of 45 acp from:
1) What will just cycle the action with a soft recoil spring to 45acp
2) 45acp
3) 45acp +P
4) 45 Super
5) 460 Rowloand equivalent loads
6) Beyond 460 Rowland loads
I have done all of these, and points in between in .1 gr increments.
The things to watch are:
1) Ammo must be powerfull enough to cylcle the action with that spring and slide mass or it will jam.
2) Ammo must be too much more than enough or the slide will batter the frame.
3) The case must be supported enough for the pressure, or the case will bulge, or worse.
Following these guide lines, I have found the level that is right for my 45acps:
1) Mauser Rifle, beyond 460 Rowland
2) Patriot pistol, 460 Rowland
3) Colt Commander, between 45 Super and 460 Rowland
4) Para Ord P10, 45 Super, Starline +P brass, 1.275", 155 gr SWC
I have had to put serious recoil springs in the Patriot and the Commander.
AF FAL
Member
4506 in 460 Rowland?
I have been looking for info on converting a S&W 4506 to 460 Rowland, anyone think this will work? I picked it up for a song to be a tinker gun and play with different chamberings.
400 CORBON is now out as I can't find a barrel manufacturer anymore, to many reliability issues claimed with the S&W in 400. Barsto has discontinued any S&W auto barrels, and all 400 CORBON barrels in the last couple months.
45 Super is not a good idea, as I have several 45's, the chance of accidentally chambering a super in a non modded gun is not worth the chance I think.
So any inputs on the 460 Rowland? Seems all the 1911's have compensators to get the extra squeeze on the round, and control recoil. Doesn't seem practical or cost efficient with the 4506. What about porting the barrel to minimize recoil a bit, or would it knock velocities down to Super or =P loads?
Any ideas/advice? Open to other chamberings as well, only requiremnt is available brass, preferrably that I don't have to form.
I have been looking for info on converting a S&W 4506 to 460 Rowland, anyone think this will work? I picked it up for a song to be a tinker gun and play with different chamberings.
400 CORBON is now out as I can't find a barrel manufacturer anymore, to many reliability issues claimed with the S&W in 400. Barsto has discontinued any S&W auto barrels, and all 400 CORBON barrels in the last couple months.
45 Super is not a good idea, as I have several 45's, the chance of accidentally chambering a super in a non modded gun is not worth the chance I think.
So any inputs on the 460 Rowland? Seems all the 1911's have compensators to get the extra squeeze on the round, and control recoil. Doesn't seem practical or cost efficient with the 4506. What about porting the barrel to minimize recoil a bit, or would it knock velocities down to Super or =P loads?
Any ideas/advice? Open to other chamberings as well, only requiremnt is available brass, preferrably that I don't have to form.
Clark
Member
You don't need 460 Rowland brass to take 460 Rowland pressure.
45acp brass is just as good.
But the extra length of 460 brass keeps the ammo from getting mixed up.
You need case support.
You need to deal with the recoil.
There may be a 45 out there with thin chamber walls, but I have not seen it. Still you need thick chamber walls. The P3AT and CZ52 are the only pistols I have seen with chamber walls so thin it could be a problem.
I have gone past 460 Rowland pressure and performance in a small 45acp pistol with 45acp brass, and I got a flinch.
I built a 42 pound triple recoil spring assembly and the chamber came up empty.
I doubled up the mag springs and the chamber came up loaded.
Now I have a gun that takes a strong grip to cycle and a strong thumb to load.
But the slide stopped hitting the frame so hard, and now my flinch is gone.
If you are going to do something like that you need to have your wits about you. Like climbing a mountain, mistakes can get you hurt. You must be able to think. Making up your own rules as you go, means mistakes can get you hurt.
What does it all mean?
If you don't know what you're doing, don't do it.
45acp brass is just as good.
But the extra length of 460 brass keeps the ammo from getting mixed up.
You need case support.
You need to deal with the recoil.
There may be a 45 out there with thin chamber walls, but I have not seen it. Still you need thick chamber walls. The P3AT and CZ52 are the only pistols I have seen with chamber walls so thin it could be a problem.
I have gone past 460 Rowland pressure and performance in a small 45acp pistol with 45acp brass, and I got a flinch.
I built a 42 pound triple recoil spring assembly and the chamber came up empty.
I doubled up the mag springs and the chamber came up loaded.
Now I have a gun that takes a strong grip to cycle and a strong thumb to load.
But the slide stopped hitting the frame so hard, and now my flinch is gone.
If you are going to do something like that you need to have your wits about you. Like climbing a mountain, mistakes can get you hurt. You must be able to think. Making up your own rules as you go, means mistakes can get you hurt.
What does it all mean?
If you don't know what you're doing, don't do it.
Close call
After reading the Real guns article with its assurances the 1911 was a great overly robust design, I developed a .45 Super load using reloader 7 and Hornady 200gr XTPs at ~1350fps. This was to be for hog hunting with my Springfield GM. I only shot about 100 rounds. Enough to develop the load and be mostly assured that everything was going to work okay.
After recently reading Kuhnhausen, I did a blueprint of my Springer and found a number of glaring deficiencies. The most egregious, was the upper barrel lugs were cut only 0.038" deep. They only had about 85% engagement, and they were not equalized, with only lug #1 doing all the work. So only about 15% of my potential engagement surface was actually working.
Very lucky I didn't break anything.
After reading the Real guns article with its assurances the 1911 was a great overly robust design, I developed a .45 Super load using reloader 7 and Hornady 200gr XTPs at ~1350fps. This was to be for hog hunting with my Springfield GM. I only shot about 100 rounds. Enough to develop the load and be mostly assured that everything was going to work okay.
After recently reading Kuhnhausen, I did a blueprint of my Springer and found a number of glaring deficiencies. The most egregious, was the upper barrel lugs were cut only 0.038" deep. They only had about 85% engagement, and they were not equalized, with only lug #1 doing all the work. So only about 15% of my potential engagement surface was actually working.
Very lucky I didn't break anything.
madmike
Member
What technique did they use to measure that in 1904?
grendelbane
Member
They would have used a ballistic pendulum. This method dates back to the 18th century, I believe.
http://www.thehighroad.org/showthread.php?t=102485
Google Boulenge, and you will find a lot of good information on early ballistics measurement.
Some of those numbers were exaggerated. I don't think this was because of the inaccuracy of the measurements, but more likely it was the result of overly aggressive marketing.
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